U.S. Pat. No. 4,421,073 dated Dec. 20, 1983 and titled INTERNAL COMBUSTION ROTARY ENGINE by ARREGUI et al, the present applicant being one of the four co-inventors, describes an engine block which is rotatably mounted within a stationary casing which closes the open outer ends of the piston chambers. It has been found in practice that it is very difficult to seal the piston chambers at their interface with the casing.
U.S. Pat. No. 4,645,428 by the same four co-inventors and dated Feb. 24, 1987 for RADIAL PISTON PUMP, describes a device which is not suitable for use as an internal combustion engine even if the basic operating principle is similar to that of the engine in accordance with the present invention.